Spade-type boring bit having chamfered corner portions



FIG. 1 is a front perspective view of a first embodiment of a spade-type boring bit having chamfered corner portions embodying our new design;

FIG. 2 is a rear elevational view thereof, taken from the side opposite that illustrated in FIG. 1;

FIG. 3 is a side elevational view thereof, taken from the side opposite that illustrated in FIG. 1;

FIG. 4 is a slightly enlarged top plan view thereof;

FIG. 5 is a slightly enlarged bottom plan view thereof;

FIG. 6 is a front perspective view of a second embodiment of our new design;

FIG. 7 is a rear elevational view thereof, taken from the side opposite that illustrated in FIG. 6;

FIG. 8 is a side elevational view thereof, taken from the side opposite that illustrated in FIG. 6;

FIG. 9 is a slightly enlarged top plan view thereof; and,

FIG. 10 is a slightly enlarged bottom plan view thereof.

The broken lines in the figures are shown for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a spade-type boring bit having chamfered corner portions, as shown and described. 